1. Field of the Invention
This invention relates to a device for uniting components one to another and may comprise a closure for a bag.
2. Description of the Prior Art
It is known to provide open bags made of synthetic plastics film material in which contents are inserted and the bags subsequently closed.
Various forms of closure have been used and proposed for such bags, and a common form of closure comprises a portion of pressure sensitive contact adhesive provided on a surface of the material of which a bag is formed, the adhesive being located at an opening of the bag.
A disadvantage of bags having closure means in the form of pressure sensitive contact adhesive is that it is necessary to mask the adhesive during transit and storage of the bags prior to use, the bags generally being stacked, since otherwise the bags will adhere one to another. Masking of adhesive generally is effected by covering the adhesive with a tape having a release coating in contact with the adhesive so that, when it is necessary to effect closure of a bag, the masking tape can be peeled from the adhesive, which remains on the material of the bag, to expose the adhesive.
Apart from the cost of providing masking tape, bags having masking tape covering adhesive closure means have a disadvantage in that it is necessary to remove the masking tape before closure of a bag can be effected. It is desirable, therefore, to provide a device for uniting components one to another which device may comprise a closure for a bag in which pressure sensitive contact adhesive is not covered by masking tape and thereby is less expensive to produce and less time consuming to effect closure thereof compared with closures for bags known hitherto.
One such device is known which comprises a first component, such as a panel of a bag, a second component, such as a second panel of the bag facing the first panel, the second component having an elongate opening therein and a membrane having pressure sensitive contact adhesive thereon, the membrane being united with a first surface of the second component such that the adhesive bridges the opening and contacts the surface of the first component through the opening when that surface is adjacent the second surface of the second component remote from the membrane. An example of such a device is described in French Patent No. 2,345,355 (Janowski) with reference to FIG. 1 of the drawings accompanying the specification of that patent.
A disadvantage of such device is that whenever the said surface of the first component, or indeed any other surface of another component for example, is located adjacent the second surface of the second component, the said surface of the first component is contacted by the adhesive. If the first and second components are panels of a bag, such contact can result in premature and unwanted closing of the bag or, if the other surface comprises a surface of an article being inserted into or removed from the bag, in contamination of the article by the adhesive and/or contamination of the adhesive by the article.